Saturday, March 27, 2010

Not being a climate change specialist myself, I have been wondering why biomass energy burned as fuel in households generally does not show up in the climate change calculations. For instance typical families burning 0.18 tons LPG for cooking per year actually gets included in the estimates of greenhouse gas emissions and yet a similar family burning close to 2 tons of fuelwood per year is not considered as producing any greenhouse gas emissions.

According to my back of the envelope calculations people mostly in developing counties burn about 730 million tons of biomass per year for cooking and this amounts to about 1 billion tons of CO2 emitted into the atmosphere. This burning emits about 3%-4% of the world’s total CO2 emissions which according to some estimates is about 28 billion tons per year coming mostly from developed countries. World experts generally do not include the emissions from burning fuelwood, straw or dung because they are renewable. Thus, putting black carbon, health and other benefits aside, from a climate perspective the emissions from burning biomass are generally are considered to be climate neutral.

Sunday, March 21, 2010

I just read a very fascinating report called Evaluation of Manufactured Wood-Burning Stoves in Dabaab Refugee Camps Kenya by the Berkeley Air Monitoring Group. This report compares the performance of many of the stoves that were mentioned in a previous post on next generation stoves. As part of this blog, from time to time I will provide a brief review of interesting studies or conferences. This is not meant to be a peer review, but rather the remarks will be my own personal views. Others can express their opinions by commenting on these review postings.

This study reminded me that measuring the efficiency of improved stoves is not a simple task, but it is quite necessary. Often there are evaluations of single stove interventions, but comparative reviews are not as common. Testing methods actually have been a point of great contention and debate because some favor certain types of stoves over others. Such a lack of objective information or comparative testing results has been hampering improved stoves in developing countries for many years. Millions of dollars are given for stove programs and the monitoring and evaluation is often not very credible.

This study actually lays out its methods very clearly describing the testing environment in detail. There also were focus discussion groups with the cooks, a research technique that is highly recommended and often lacking in other work on stoves. The technical part of the study evaluates multiple manufactured stoves using a method called the controlled cooking test. Under this test the same amount of typical local food is cooked with measured amounts of fuelwood. The results are reported in kilograms of the fuelwood required for standardized cooking of one kilogram of food. Again, this is obviously a contrived environment, but it is a standard method that has been used for more than 25 years.

Saturday, March 13, 2010

The pace of rural electrification over much of the developing world has been painfully slow, especially in South Asia and Africa. Rural electrification programs can undoubtedly face major obstacles. The low population densities in rural areas result in high capital and operating costs for electricity companies. Consumers are often poor and their electricity consumption low. This post is on grid rural electrification and there will be a similar future post on offgrid rural electrification.

The Challenge of Rural Electrification: D. Barnes

Yet in spite of these problems, many countries have been quietly and successfully providing electricity to rural areas. In Thailand, well over 90 percent of rural people have a supply. In Costa Rica, cooperatives and the government power utility provide electricity to nearly 100% percent of the rural population. In Tunisia, over 90% percent of rural households already have a supply. In studying countries like these and others there appear to be 8 steps to achieving successful rural electrification. These steps are taken from my book called The Challenge of Rural Electrification: Strategies for Developing Countries.that examined 10 successful programs from around the world including the developed countries of the United States and Ireland. I know that it appears these programs are in middle to high income countries, but many were low income when they initiated their programs.

Saturday, March 6, 2010

In developed countries we take electric lights for granted. We throw a switch, and presto the room lights up from ceiling to floor. But we all have experienced life without electricity during periodic brownouts and blackouts when we get out the candles for several hours. Unfortunately for the approximately 1.5 billion people without electricity in developing countries, there is no switch to throw.

One of the major benefits of rural electrification in developing countries is household lighting. In fact, people often ask my advice on how to measure such benefits. The issues can range from sampling to questionnaire design to sampling techniques. Thus, this is the first in a series of blogs which I will call Survey Design. For the first in this series, I am going to focus on how to measure household lighting. Stay tuned for more on surveys.

Lighting Efficinecy: Credit D. Barnes

People without electricity in developing countries generally light their homes with candles or kerosene wick lamps. The light given from a kerosene lamp is very dim and not great for reading and there is a good reason for this. For measuring lighting in households it is essential to understand that light is measured in lumens. A lumen is a unit used for measuring brightness. A kerosene lamp or a candle gives off about 11 lumens (see chart). By comparison a 100 watt incandescent light bulb provides 1,600 lumens, which is labeled on most packaging. The figure demonstrates that electric lights are much more efficient in converting energy into light. In a measurement study on lighting output it was found that a 100 watt incandescent light bulb typically found in developing countries actually turned out to provide 12.8 kilolumens of light per kilowatt hour compared to 0.1 kilolumens per kilowatt hour for a kerosene lamp. Fluorescent lights are even more efficient.

The reason for the difference between the lumen levels listed on the label on a light bulb package and the testing results has to do with the measurement environment. Actual lumen levels vary based on factors such as reflectors, lenses and location of the light in a room.

Efficiency of Lamps: Credit D. Barnes

How does that have an impact on household lighting? I will demonstrate this by using the results of a household energy survey from Peru. These results are based on actual use of various lighting sources for a national rural sample of 6000 households. As can be seen, the candle and kerosene lamps provide barely enough light to walk around the house. Car Batteries are used for lighting by households with higher incomes but without grid electricity and they provide more light. Due to the efficiency of converting energy into light, electricity from the grid is the best source for household lighting for households who participated in the survey in rural Peru. One may wonder why these household without electricity do not use household photovoltaic systems, but that will be the subject of another post.